Liquid crystal alignment agent for photo-alignment, aligning member, and retardation member

A liquid crystal alignment agent for photo-alignment for providing an aligning member has excellent photoreaction efficiency and is capable of aligning polymerizable liquid crystals with high sensitivity. A liquid crystal alignment agent for photo-alignment includes (A) a resin having a side chain including a structure of Formula (1) and (B) a compound of Formula (2), an alignment member obtained from the liquid crystal alignment agent, and a retardation member: wherein X1 is a benzene ring which may be arbitrarily substituted with an substituent, R is a substituent selected from OH and NH2, R1, R2, R3, R4 and R5 are each independently a substituent selected from a hydrogen atom, a halogen atom, C1-6 alkyl, C1-6 haloalkyl, etc., and n is an integer of 0 or 1.